1 files changed, 38 insertions, 12 deletions

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 4f1fc81112e6..05085beb83db 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -194,8 +194,7 @@ static inline struct tty_struct *file_tty(struct file *file)
         return ((struct tty_file_private *)file->private_data)->tty;
 }
 
-/* Associate a new file with the tty structure */
-int tty_add_file(struct tty_struct *tty, struct file *file)
+int tty_alloc_file(struct file *file)
 {
         struct tty_file_private *priv;
 
@@ -203,15 +202,36 @@ int tty_add_file(struct tty_struct *tty, struct file *file)
         if (!priv)
                 return -ENOMEM;
 
+        file->private_data = priv;
+
+        return 0;
+}
+
+/* Associate a new file with the tty structure */
+void tty_add_file(struct tty_struct *tty, struct file *file)
+{
+        struct tty_file_private *priv = file->private_data;
+
         priv->tty = tty;
         priv->file = file;
-        file->private_data = priv;
 
         spin_lock(&tty_files_lock);
         list_add(&priv->list, &tty->tty_files);
         spin_unlock(&tty_files_lock);
+}
 
-        return 0;
+/**
+ * tty_free_file - free file->private_data
+ *
+ * This shall be used only for fail path handling when tty_add_file was not
+ * called yet.
+ */
+void tty_free_file(struct file *file)
+{
+        struct tty_file_private *priv = file->private_data;
+
+        file->private_data = NULL;
+        kfree(priv);
 }
 
 /* Delete file from its tty */
@@ -222,8 +242,7 @@ void tty_del_file(struct file *file)
         spin_lock(&tty_files_lock);
         list_del(&priv->list);
         spin_unlock(&tty_files_lock);
-        file->private_data = NULL;
-        kfree(priv);
+        tty_free_file(file);
 }
 
 
@@ -1811,6 +1830,10 @@ static int tty_open(struct inode *inode, struct file *filp)
         nonseekable_open(inode, filp);
 
 retry_open:
+        retval = tty_alloc_file(filp);
+        if (retval)
+                return -ENOMEM;
+
         noctty = filp->f_flags & O_NOCTTY;
         index  = -1;
         retval = 0;
@@ -1823,6 +1846,7 @@ retry_open:
                 if (!tty) {
                         tty_unlock();
                         mutex_unlock(&tty_mutex);
+                        tty_free_file(filp);
                         return -ENXIO;
                 }
                 driver = tty_driver_kref_get(tty->driver);
@@ -1855,6 +1879,7 @@ retry_open:
                 }
                 tty_unlock();
                 mutex_unlock(&tty_mutex);
+                tty_free_file(filp);
                 return -ENODEV;
         }
 
@@ -1862,6 +1887,7 @@ retry_open:
         if (!driver) {
                 tty_unlock();
                 mutex_unlock(&tty_mutex);
+                tty_free_file(filp);
                 return -ENODEV;
         }
 got_driver:
@@ -1872,6 +1898,8 @@ got_driver:
                 if (IS_ERR(tty)) {
                         tty_unlock();
                         mutex_unlock(&tty_mutex);
+                        tty_driver_kref_put(driver);
+                        tty_free_file(filp);
                         return PTR_ERR(tty);
                 }
         }
@@ -1887,15 +1915,11 @@ got_driver:
         tty_driver_kref_put(driver);
         if (IS_ERR(tty)) {
                 tty_unlock();
+                tty_free_file(filp);
                 return PTR_ERR(tty);
         }
 
-        retval = tty_add_file(tty, filp);
-        if (retval) {
-                tty_unlock();
-                tty_release(inode, filp);
-                return retval;
-        }
+        tty_add_file(tty, filp);
 
         check_tty_count(tty, "tty_open");
         if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
@@ -2716,6 +2740,8 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
         ld = tty_ldisc_ref_wait(tty);
         if (ld->ops->compat_ioctl)
                 retval = ld->ops->compat_ioctl(tty, file, cmd, arg);
+        else
+                retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg);
         tty_ldisc_deref(ld);
 
         return retval;